Interstitial cystitis is a bladder condition associated with discomfort and pain elicited by urinary irritants, causing urgency for, and increased frequency of, urination. Because its cause is poorly understood, the development of useful treatments has followed approaches that are largely empirical and even haphazard, and these approaches have failed to yield more than a few useful therapeutic agents and treatments. As described by Sant and La Rock in Interstitial Cystitis, Vol. 21 (1), February 1994 at p.73, current therapies include pharmacotherapy, with intravesical use of dimethyl sulfoxide being the only therapy approved by the FDA. Still, a variety of other agents are in use to treat symptoms of interstitial cystitis, either alone or in combination with DMSO. Such agents include sodium oxychlorosene (Clorpactin), heparin, hyaluronic acid, steroid, sodium bicarbonate, silver nitrate, sodium pentosanpolysulfate, cromolyn sodium, lidocaine and doxorubicin. Many of these agents can be delivered orally, but to be effective are most typically delivered by instillation either as monotherapy, combination therapy or sequential therapy. These agents and therapies target the bladder mucosal lining, and provide symptomatic relief of pain, frequency and urgency. Of these therapies, however, few offer relief over sustained periods.
There is a need to provide, on a cost-effective basis, agents and therapies that are useful to treat cystitis, including interstitial cystitis and related conditions of the bladder and urinary tract that result from an eroded mucosal lining. There is also a need to provide methods by which patients can be screened to reveal therapeutic agents effective to treat that patient's particular condition. It is accordingly an object of the present invention to provide such a diagnostic screening method.